1. Field of the Invention
The present invention relates to a wrist blood pressure gauge that provides a way for a cuff worn on the wrist during blood pressure measurement to be adjusted to the height of the heart.
2. Description of the Related Art
Although not an issue when measuring blood pressure in the upper arm, when blood pressure is measured in the wrist, the height of the wrist in which the blood pressure is being measured must be substantially the same as the height of the heart. The reason for this is that the measurement results are affected by the water head pressure difference when the wrist and heart are at different heights, and an accurate measurement cannot be obtained.
Conventionally, when blood pressure is measured using this type of wrist blood pressure gauge in the past, the cuff is first placed on the wrist, after which the elbow is placed on a table, for example, the forearm is gradually raised until the height of the cuff is visually confirmed to be even with the height of the heart, and blood pressure measurement is started in this position.
However, when the heights are matched visually, the height can be uneven in each measurement, and there is a risk of fluctuation in the measured value.
In order to overcome these drawbacks, the wrist blood pressure gauge has been proposed in Japanese Patent Application Laid-Open Nos. 7-289527 and 8-580, in which a device for detecting a tilt angle is provided to the cuff, and the bend angle of the elbow is detected by the detection device, whereby the height of the wrist is estimated when the elbow is bent.